Catalyst system, method for the production thereof, and the utilization thereof for the polymerization of olefins

ABSTRACT

A catalyst system with at least one specifically substituted metallocene which contains a cationic group as a substituent, a process for preparing such a catalyst system and its use in the polymerization of olefins. In particular, said catalyst system has (a) at least one support, (b) at least one cocatalyst and (c) at least one metallocene of the formula                    
     where M 1 , R 1 , R 2 , R 3 , m, m′, A, k and X are defined herein.

The present invention relates to catalyst systems comprisingspecifically substituted metallocenes which can advantageously be usedin olefin polymerization and to a process for preparing them and also totheir use in the polymerization of olefins.

Processes for preparing polyolefins with the aid of soluble, homogeneouscatalyst systems comprising a transition metal component of themetallocene type and a cocatalyst component such as an aluminoxane, aLewis acid or an ionic compound are known. These catalysts have a highactivity and give polymers and copolymers having a narrow molar massdistribution.

In polymerization processes using soluble, homogeneous catalyst systems,thick deposits form on reactor walls and stirrer if the polymer isobtained as a solid. These deposits are always formed by agglomerationof the polymer particles when metallocene and/or cocatalyst are presentin dissolved form in the suspension. Such deposits in the reactorsystems have to be removed regularly, since they rapidly reachconsiderable thicknesses, have a high strength and prevent heat transferto the cooling medium. Such homogeneous catalyst systems cannot be usedindustrially in modern polymerization processes in liquid monomer or inthe gas phase.

To avoid deposit formation in the reactor, supported catalyst systems inwhich the metallocene and/or the aluminum compound serving as cocatalystare fixed to an inorganic support material have been proposed.

EP-A-0,576,970 discloses metallocenes and corresponding supportedcatalyst systems.

However, a frequent problem in the industrial use of supported catalystsystems is the leaching of the metallocene component from the supportmaterial, which results, for example, in undesirable deposit formationin the reactor.

It is an object of the present invention to find novel catalyst systemsin which the metallocene component can be firmly fixed to the supportand cannot be leached from the support material under industriallyrelevant polymerization conditions.

We have found that this object is achieved by catalyst systemscomprising at least one specifically substituted metallocene whichcontains a cationic group as substituent.

The present invention provides a catalyst system comprising

a) at least one support,

b) at least one cocatalyst and

c) at least one metallocene of the formula (I)

 where

M¹ is a transition metal of Group 4 of the Periodic Table of theElements, for example titanium, zirconium or hafnium, preferablyzirconium,

R¹ and R² are identical or different and are each a hydrogen atom, aC₁-C₂₀ group, preferably a C₁-C₂₀-alkyl group, a C₆-C₁₄-aryl group, aC₂-C₂₀-alkenyl group, a C₂-C₂₀-alkynyl group, or a C₇-C₂₀-alkylarylgroup, each of which may bear one or more identical or different halogenatoms as substituents, a halogen atom, an —SiMe₃ group or an OSiMe₃group, particularly preferably hydrogen, methyl, ethyl, n-propyl,isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, branchedpentyl, n-hexyl, branched hexyl, cyclohexyl or benzyl,

R³ are identical or different and are each a hydrogen atom or a C₁-C₄₀group, preferably a C₁-C₂₀-alkyl group which may be substituted, inparticular methyl, ethyl, trifluoroethyl, n-propyl, isopropyl, n-butyl,sec-butyl, isobutyl, tert-butyl, pentyl, hexyl, octyl, cyclopropyl,cyclopentyl or cyclohexyl, a C₆-C₁₄-aryl group which may be substituted,for example phenyl, tolyl, xylyl, tert-butylphenyl, ethylphenyl,trifluoromethylphenyl, bis(trifluoromethyl)phenyl, methoxyphenyl,fluorophenyl, dimethylaminophenyl, trimethylammoniumphenyl iodide,dimethylsulfoniumphenyl bromide, triethylphosphoniumphenyl triflate,naphthyl, acenaphthyl, phenanthrenyl or anthracenyl, a C₂-C₂₀-alkenylgroup, a C₂-C₂₀-alkynyl group, a C₇-C₂₀-alkylaryl group, a halogen atom,an SiMe₃ group, an OSiMe₃ group or a C₁-C₂₀-heterocyclic group which maybe substituted, where the term heteroatom encompasses all elements withthe exception of carbon and hydrogen and preferably refers to an atom ofgroup 14, 15 or 16 of the Periodic Table of the Elements, and tworadicals R³ may form a monocyclic or polycyclic ring system which may inturn be substituted, where at least one of the radicals R¹, R², R³ is acationic group (—DE_(L))⁺Y⁻,

where

D is an atom of group 15 or 16 of the Periodic Table of the Elements,preferably nitrogen, phosphorus, oxygen or sulfur,

E are identical or different and are each a hydrogen atom, a C₁-C₂₀group, preferably a C₁-C₂₀-alkyl group, a C₆-C₁₄-aryl group, aC₂-C₂₀-alkenyl group, a C₂-C₂₀-alkynyl group or a C₇-C₂₀-alkylarylgroup, a trialkylsilyl group, a triarylsilyl group or an alkylarylsilylgroup, which may each be substituted, and two radicals E may form amonocyclic or polycyclic ring system which may in turn be substituted,particularly preferably a hydrogen atom, methyl, ethyl, propyl, butyl,allyl, benzyl, methoxymethyl, benzyloxymethyl, 2-methoxyethoxymethyl,2-trimethylsilylethoxymethyl or trimethylsilyl,

L is 3 when D is an atom of group 15 of the Periodic Table of theElements and is 2 when D is an atom of group 16 of the Periodic Table ofthe Elements,

Y is halogen, C₁-C₁₀-alkylsulfonate, C₁-C₁₀-haloalkylsulfonate,C₆-C₂₀-arylsulfonate, C₆-C₂₀-haloarylsulfonate,C₇-C₂₀-alkylarylsulfonate, C₁-C₂₀-haloalkylcarboxylate,C₁-C₁₀-alkylsulfate, tetrafluoroborate, hexafluorophosphate,hexafluoroantimonate or hexafluoroarsenate, preferably chloride,bromide, iodide, triflate, mesylate, tosylate, benzenesulfonate,trifluoroacetate, methyl sulfate, tetrafluoroborate orhexafluorophosphate,

m is an integer less than or equal to 4 and greater than or equal to 1,preferably 1 or 2, particularly preferably 1,

m′ is an integer less than or equal to 4 and greater than or equal to 1,preferably 1 or 2, particularly preferably 1,

k is zero or 1, with the metallocene being unbridged when k=0 and themetallocene being bridged when k=1,

A is a bridge of the formula

or ═BR⁴, AlR⁴, —S—, —SO—, —SO₂—, ═NR⁴, ═PR⁴, ═P(O)R⁴, o-phenylene or2,2′-biphenylene, where

M² is carbon, silicon, germanium, tin, nitrogen or phosphorus,preferably carbon, silicon or germanium, in particular carbon orsilicon,

o is 1, 2, 3 or 4, preferably 1 or 2,

R⁴ and R⁵ are identical or different and are each, independently of oneanother, a hydrogen atom, halogen, a C₁-C₂₀ group, preferably aC₁-C₂₀-alkyl, in particular methyl, a C₆-C₁₄-aryl, in particular phenylor naphthyl, a C₁-C₁₀-alkoxy, a C₂-C₁₀-alkenyl, a C₇-C₂₀-arylalkyl, aC₇-C₂₀-alkylaryl, a C₆-C₁₀-aryloxy, a C₁-C₁₀-fluoroalkyl, aC₆-C₁₀-haloaryl, a C₂-C₁₀-alkynyl, a C₃-C₂₀-alkylsilyl, in particulartrimethylsilyl, triethylsilyl or tert-butyidimethylsilyl, aC₃-C₂₀-arylsilyl, in particular triphenylsilyl, or aC₃-C₂₀-alkylarylsilyl, in particular dimethylphenylsilyl, diphenylsilylor diphenyl-tert-butylsilyl, and R⁴ and R⁵ may form a monocyclic orpolycyclic ring system.

A is preferably dimethylsilanediyl, dimethylgermanediyl, ethylidene,methylethylidene, 1,1-dimethylethylidene, 1,2-dimethylethylidene,tetramethylethylidene, isopropylidene, phenylmethylmethylidene ordiphenylmethylidene, particularly preferably dimethylsilanediyl orethylidene.

The radicals X are identical or different and are each a hydrogen atom,a halogen atom such as fluorine, chlorine, bromine or iodine, a hydroxylgroup, a C₁-C₁₀-alkyl group such as methyl, ethyl, propyl, isopropyl,n-butyl, isobutyl, sec-butyl, tert-butyl, hexyl or cyclohexyl, aC₆-C₁₅-aryl group such as phenyl or naphthyl, a C₁-C₁₀-alkoxy group suchas methoxy, ethoxy or tert-butoxy, a C₆-C₁₅-aryloxy group or a benzylgroup, preferably a chlorine atom, a fluorine atom, a methyl group or abenzyl group, particularly preferably a chlorine atom or a methyl group.

Particularly preferred metallocenes of the formula (I) have the formula(I*),

where

M¹, A, R¹, k and X are as defined for formula (I) and

R⁶ are identical or different and are each a hydrogen atom or a C₁-C₄₀group, preferably a C₁-C₂₀-alkyl group which may be substituted, inparticular methyl, ethyl, trifluoromethyl, trifluoroethyl, n- propyl,isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl,octyl, cyclopropyl, cyclopentyl or cyclohexyl, a C₆-C₁₄-aryl group whichmay be substituted, in particular phenyl, a C₂-C₂₀-alkynyl group, aC₇-C₂₀-alkylaryl group, halogen, an OR⁴ group, an SiR⁴ ₃ group, an NR⁴ ₂group or an SR⁴ group, and two radicals R⁴ and R⁶, each or together, mayform a monocyclic or polycyclic ring system which may in turn besubstituted, where R⁴ is as defined for formula (I), and at least one ofthe radicals R⁶ bears a cationic group (—DE_(L))⁺Y⁻,

where D, E, L and Y are as defined for formula (I),

q is an integer less than or equal to 5 and greater than or equal to 1,preferably 1 or 2, particularly preferably 1,

q′ is an integer less than or equal to 5 and greater than or equal to 1,preferably 1 or 2, particularly preferably 1.

Illustrative but nonrestrictive examples of novel metallocenes of theformula (I) are:

dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorotitaniumdiiodide

dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorohafniumdiiodide

dimethylsilanediylbis(2-methyl-4-(3′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(2′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(3′,5′-bis(trimethylammonium)phenyl)indenyl)dichlorozirconiumtetraiodide

dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumnaphthyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumditosylate

dimethylsilanediylbis(2-ethyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumditriflate

dimethylsilanediylbis(2-methyl-4-(4′-dimethylammoniumphenyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumbistetrafluoroborate

dimethylsilanediylbis(2-methyl-4-(4′-N-methyl-N-pyrrolidinophenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(4′-dimethylammoniumphenyl)indenyl)dichlorotitaniumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-dimethyl(methoxymethyl)ammoniumphenyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-dimethyl(2″-methoxyethoxymethyl)ammoniumphenyl)indenyl)dichlorozirconium dichloride

dimethylsilanediylbis(2-methyl-4-(4′-dimethyl(benzyloxymethyl)ammoniumphenyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-dimethyl-(2″-trimethylsilylethoxymethyl)ammoniumphenyl)indenyl)dichlorohafniumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-dimethylbenzylammoniumphenyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-dimethylallylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-ethyl-4-(4′-dimethyl-(2″-trimethylsilylethoxymethyl)ammoniumphenyl)indenyl)dichlorohafniumdichloride

dimethylsilanediylbis(2-ethyl-4-(4′-dimethylbenzylammoniumphenyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-ethyl-4-(4′-dimethylallylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-ethyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-n-butyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-isopropyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-isobutyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumditriflate

dimethylsilanediylbis(2-ethyl-4-(4′-triethylphosphoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-ethyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-(3′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-(2′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-(3′,5′-bis(dimethylsulfonium)phenyl)indenyl)dichlorozirconiumtetrabromide

dimethylsilanediylbis(2-methyl-4-(4′-dibenzylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-(4′-methyl(methoxymethyl)sulfoniumphenyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-diallylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-(3′-diphenylethylphosphoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(3′-trimethylphosphoniumphenyl)indenyl)dichlorozirconiumditriflate

methylphenylsilanediylbis(2-isobutyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumditosylate

1,2-ethanediylbis(2-methyl-4-(3′-dimethylammoniumphenyl)indenyl)dichlorozirconiumbistrifluoroacetate

1,2-ethanediylbis(2-methyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide

1,2-ethanediylbis(2-methyl-4-(3′-diphenylethylphosphoniumphenyl)indenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-5-trimethylammoniumindenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-5-trimethylphosphoniumindenyl)dichlorozirconiumdichloride

1,2-ethanediylbis(2-methyl-4-dimethylbenzy,ammoniumindenyl)dichlorozirconiumdibromide

1,2-ethanediylbis(2-methyl-4-phenyl-5-dimethylbenzylammoniumindenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-phenyl-6-trimethylammoniumindenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-5-dimethylsulfoniumindenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-methyl-4-(4′-(2″-trimethylammoniumethyl)phenylindenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(4′-(3″-dimethylsulfoniumpropyl)phenylindenyl)dichlorozirconiumdiiodide

dimethylsilanediylbis(2-methyl-4-(3′-(2″-trimethylammoniumethyl)phenylindenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-methyl-4-(2′-trimethylammoniumethyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-(2′-trimethylammoniumethyl)indenyl)dichlorozirconiumdichloride

dimethylsilanediylbis(2-(2′-trimethylammoniumethyl)-4-phenylindenyl)dichlorozirconiumdibromide

dimethylsilanediylbis(2-(2′-dimethylsulfoniumethyl)-4,6-dimethylindenyl)dichlorozirconiumdiiodide

The catalyst system of the present invention comprises at least onecocatalyst (component b). The cocatalyst component which may, accordingto the present invention, be present in the catalyst system comprises atleast one compound such as an aluminoxane or a Lewis acid or an ioniccompound which reacts with a metallocene to convert it into a cationiccompound.

As aluminoxane, preference is given to using a compound of the formulaII

(R AlO)_(p)  (II).

Aluminoxanes may be, for example, cyclic as in formula (III)

or linear as in formula (IV)

or of the cluster type as in formula (V), as are described in theliterature (JACS 117 (1995), 6465-74, Organometallics 13 (1994),2957-2969).

The radicals R in the formulae (II), (III), (IV) and (V) may beidentical or different and may be a C₁-C₂₀-hydrocarbon group preferablya C₁-C₆-alkyl group, a C₆-C₁₈-aryl group or benzyl, or hydrogen, and pis an integer from 2 to 50, preferably from 10 to 35.

The radicals R are preferably identical and are methyl, isobutyl,n-butyl, phenyl or benzyl, particularly preferably methyl.

If the radicals R are different, they are preferably methyl andhydrogen, methyl and isobutyl or methyl and n-butyl, where hydrogen orisobutyl or n-butyl are preferably present in a proportion of 0.01-40%(number of radicals R).

The aluminoxane can be prepared in various ways by known methods. One ofthe methods is, for example, reacting an aluminum-hydrocarbon compoundand/or a hydridoaluminum-hydrocarbon compound with water (gaseous,solid, liquid or bound-for example as water of crystallization) in aninert solvent (e.g. toluene). To prepare an aluminoxane having differentalkyl groups R, two different trialkylaluminums (AlR₃ +AlR′₃)corresponding to the desired composition and reactivity are reacted withwater (cf. S. Pasynkiewicz, Polyhedron 9 (1990) 429 and EP-A-0,302,424).

Regardless of the method of preparation, all aluminoxane solutions havea variable content of unreacted aluminum starting compound which ispresent in free form or as adduct.

As Lewis acid, preference is given to using at least one organoboron ororganoaluminum compound containing C₁-C₂₀ groups such as branched orunbranched alkyl or haloalkyl, e.g. methyl, propyl, isopropyl, isobutylor trifluoromethyl, unsaturated groups such as aryl or haloaryl, e.g.phenyl, tolyl, benzyl, p-fluorophenyl, 3,5-difluorophenyl,pentachlorophenyl, pentafluorophenyl, 3,4,5-trifluorophenyl or3,5-di(trifluoromethyl)phenyl.

Examples of Lewis acids are trimethylaluminum, triethylaluminum,triisobutylaluminum, tributylaluminum, trifluoroborane, triphenylborane,tris(4-fluorophenyl)borane, tris(3,5-difluorophenyl)borane,tris(4-fluoromethylphenyl)borane, tris(pentafluorophenyl) borane,tris(tolyl)borane, tris(3,5-dimethylphenyl)borane,tris(3,5-difluorophenyl)borane and/or tris(3,4,5-trifluorophenyl)borane.Very particular preference is given to tris(pentafluorophenyl)borane.

As ionic cocatalysts, preference is given to using compounds whichcontain a noncoordinating anion, for exampletetrakis(pentafluorophenyl)borates, tetraphenylborates, SbF₆—, CF₃SO₃—or ClO₄—. As cationic counterion, use is made of Lewis bases such asmethylamine, aniline, dimethylamine, diethylamine, N-methylaniline,diphenylamine, N,N-dimethylaniline, trimethylamine, triethylamine,tri-n-butylamine, methyidiphenylamine, pyridine,p-bromo-N,N-dimethylaniline, p-nitro-N,N-dimethylaniline,triethylphosphine, triphenylphosphine, diphenylphosphine,tetrahydrothiophene and triphenylcarbenium.

Examples of such ionic compounds which can be used according to theinvention are

triethylammonium tetra(phenyl)borate

tributylammonium tetra(phenyl)borate

trimethylammonium tetra(tolyl)borate

tributylammonium tetra(tolyl)borate

tributylammonium tetra(pentafluorophenyl)borate

tributylammonium tetra(pentafluorophenyl)aluminate

tripropylammonium tetra(dimethylphenyl)borate

tributylammonium tetra(trifluoromethylphenyl)borate

tributylammonium tetra(4-fluorophenyl)aborate

N,N-dimethylanilinium tetra(phenyl)borate

N,N-diethylanilinium tetra(phenyl)borate

N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate

N,N-dimethylanilinium tetrakis(pentafluorophenyl)aluminate

di(propyl)ammonium tetrakis(pentafluorophenyl)borate

di(cyclohexyl)ammonium tetrakis(pentafluorophenyl)borate

triphenylphosphonium tetrakis(phenyl)borate

triethylphosphonium tetrakis(phenyl)borate

diphenylphosphonium tetrakis(phenyl)borate

tri(methylphenyl)phosphonium tetrakis(phenyl)borate

tri(dimethylphenyl)phosphonium tetrakis(phenyl)borate

triphenylcarbenium tetrakis(pentafluorophenyl)borate

triphenylcarbenium tetrakis(pentafluorophenyl)aluminate

triphenylcarbenium tetrakis(phenyl)aluminate

ferrocenium tetrakis(pentafluorophenyl)borate and/or

ferrocenium tetrakis(pentafluorophenyl)aluminate.

Preference is given to triphenylcarbeniumtetrakis(pentafluorophenyl)borate and/or N,N-dimethylaniliniumtetrakis(pentafluorophenyl)borate.

It is also possible to use mixtures of at least one Lewis acid and atleast one ionic compound.

Cocatalyst components which are likewise of importance are borane orcarborane compounds such as

7,8-dicarbaundecaborane(13),

undecahydrido-7,8-dimethyl-7,8-dicarbaundecaborane,

dodecahydrido-1-phenyl-1,3-dicarbanonaborane,

tri(butyl)ammonium undecahydrido-8-ethyl-7,9-dicarbaundecaborate,

4-carbanonaborane(1 4),

bis(tri(butyl)ammonium) nonaborate,

bis(tri(butyl)ammonium) undecaborate,

bis(tri(butyl)ammonium) dodecaborate,

bis(tri(butyl)ammonium) decachlorodecaborate,

tri(butyl)ammonium 1-carbadecaborate,

tri(butyl)ammonium 1-carbadodecaborate,

tri(butyl)ammonium 1-trimethylsilyl-1-carbadecaborate,

tri(butyl)ammonium bis(nonahydrido-1,3-dicarbanonaborato)cobaltate(III),

tri(butyl)ammoniumbis(undecahydrido-7,8-dicarbaundecaborato)ferrate(III).

The support component (component a) of the catalyst system of thepresent invention can be any organic or inorganic, inert solid,preferably a porous support such as talc, inorganic oxides and finelydivided polymer powders (e.g. polyolefins).

Suitable inorganic oxides may be found among the oxides of elements ofgroups 2, 3, 4, 5, 13, 14, 15 and 16 of the Periodic Table of theElements. Examples of oxides preferred as supports include silicondioxide, aluminum oxide and also mixed oxides of the two elements andcorresponding oxide mixtures. Other inorganic oxides which can be usedalone or in combination with the abovementioned preferred oxidicsupports are, for example, MgO, ZrO₂, TiO₂ or B₂O₃, to name only a few.

The support materials used have a specific surface area in the rangefrom 10 to 1000 m²/g, a pore volume in the range from 0.1to 5 ml/g and amean particle size from 1to 500 μm. Preference is given to supportshaving a specific surface area in the range from 50 to 500 μm, a porevolume in the range from 0.5 to 3.5 ml/g and a mean particle size in therange from 5 to 350 μm. Particular preference is given to supportshaving a specific surface area in the range from 200 to 400 m²/g, a porevolume in the range from 0.8 to 3.0 ml/g and a mean particle size offrom 10 to 200 μm.

If the support material used naturally has a low moisture content orresidual solvent content, dehydration or drying before use can beomitted. If this is not the case, as when using silica gel as supportmaterial, dehydration or drying is advisable. Thermal dehydration ordrying of the support material can be carried out under reduced pressureand simultaneous inert gas blanketing (e.g. nitrogen). The dryingtemperature is in the range from 100 to 1000° C., preferably from 200 to800° C. The parameter pressure is not critical in this case. Theduration of the drying process can be from 1 to 24 hours. Shorter orlonger drying times are possible, provided that equilibrium with thehydroxyl groups on the support surface can be established under theconditions chosen, which normally takes from 4 to 8 hours.

The support material can also be dehydrated or dried by chemical means,by reacting the adsorbed water and the hydroxyl groups on the surfacewith suitable passivating agents. Reaction with the passivating reagentcan convert all or some of the hydroxyl groups into a form which leadsto no negative interaction with the catalytically active centers.Suitable passivating agents are, for example, silicon halides andsilanes, e.g. silicon tetrachloride, chlorotrimethylsilane,dimethylaminotrichlorosilane, or organometallic compounds of aluminum,boron and magnesium, for example trimethylaluminum, triethylaluminum,triisobutylaluminum, triethylborane, dibutylmagnesium. Chemicaldehydration or passivation of the support material is carried out, forexample, by reacting a suspension of the support material in a suitablesolvent with the passivating reagent in pure form or as a solution in asuitable solvent with exclusion of air and moisture. Suitable solventsare, for example, aliphatic or aromatic hydrocarbons such as pentane,hexane, heptane, toluene or xylene. Passivation is carried out at from25° C. to 120° C., preferably from 50 to 70° C. Higher and lowertemperatures are possible. The reaction time is from 30 minutes to 20hours, preferably from 1 to 5 hours. After chemical dehydration iscomplete, the support material is isolated by filtration under inertconditions, washed one or more times with suitable inert solvents ashave been described above and subsequently dried in a stream of inertgas or under reduced pressure.

Organic support materials such as finely divided polyolefin powders(e.g. polyethylene, polypropylene or polystyrene) can also be used andshould likewise be freed of adhering moisture, solvent residues or otherimpurities by appropriate purification and drying operations before use.

The metallocenes used according to the present invention can be obtainedby reacting a metallocene of the formula (Ia) with a reagent EY.

The radicals R¹, R², R³, A, M¹, X, E, Y, k, m and m′ are defined as forformula (I), and R⁷ are identical or different and are each a hydrogenatom or a C₁-C₄₀ group, for example a C₁-C₂₀-alkyl group which may besubstituted, for example methyl, ethyl, trifluoroethyl, n-propyl,isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl,octyl, cyclopropyl, cyclopentyl or cyclohexyl, a C₆-C₁₄-aryl group whichmay be substituted, for example phenyl, tolyl, xylyl, tert-butylphenyl,ethylphenyl, trifluoromethylphenyl, bis(trifluoromethyl)phenyl,methoxyphenyl, fluorophenyl, dimethylaminophenyl, methylthiophenyl,diethylphosphinophenyl, naphthyl, acenaphthyl, phenanthrenyl oranthracenyl, a C₂-C₂₀-alkenyl group, a C₂-C₂₀-alkynyl group, aC₇-C₂₀-alkylaryl group, a halogen atom, an SiMe₃ group, an OSiMe₃ groupor a C₁-C₂₀-heterocyclic group, which may be substituted, where the termheteroatom refers to all elements with the exception of carbon andhydrogen and is preferably an atom of group 14, 15 or 16 of the PeriodicTable of the Elements, and two radicals R⁷ may form a monocyclic orpolycyclic ring system which may in turn be substituted, and in themetallocenes of the formula (Ia), at least one of the radicals R¹, R²,R⁷ bears or is a group DE_(L−1), where D is an atom of group 15 or 16 ofthe Periodic Table of the Elements, in particular nitrogen, phosphorus,oxygen or sulfur, and E and L are as defined for formula (I).

Metallocenes of the formula (Ia) are prepared by methods known from theliterature (e.g. EP 576 970 A1; Chem. Left., 1991, 11, p.2047 ff;Journal of Organometallic Chem., 288 (1985) 63-67 and documents citedthere).

The reagent EY is a compound capable of transferring a radical E, whereE and Y are as defined for formula (I).

Illustrative but nonrestrictive examples of the reagent EY are: methyliodide, methyl bromide, methyl chloride, methyl triflate, methyltrifluoroacetate, methyl methanesulfonate, methyl p-toluenesulfonate,dimethyl sulfate, trimethyloxonium tetrafluoroborate, trimethyloxoniumhexafluorophosphate, ethyl iodide, ethyl bromide, ethyl chloride,triethyloxonium tetrafluoroborate, triethyloxonium hexafluorophosphate,propyl iodide, propyl bromide, propyl triflate, butyl bromide, butyliodide, butyl chloride, pentyl bromide, octyl bromide, benzyl chloride,benzyl bromide, benzyl triflate, allyl bromide, allyl chloride,p-methoxybenzyl chloride, trimethylsilyl chloride, trimethylsilylbromide, trimethylsilyl iodide, trimethylsilyl triflate,tert-butyldimethylsilyl chloride, tert-butyidimethylsilyl triflate,triphenylsilyl chloride, triphenylsilyl iodide, triphenylsilyl triflate,methoxymethyl chloride (MOMCl), 2-methoxyethoxymethyl chloride (MEMCl),2-trimethylsilylethoxymethyl chloride (SEMCl), benzyloxymethyl chloride(BOMCl), hydrogen fluoride, hydrogen chloride, hydrogen bromide,hydrogen iodide, trifluoroacetic acid, methanesulfonic acid,trifluoromethanesulfonic acid, p-toluenesulfonic acid, sulfuric acid,perchloric acid, acetic acid, triethylamine hydrochloride,trimethylamine hydrofluoride, tetrafluoroboric acid diethyl etherate andhexafluorophosphoric acid.

The process of the present invention can be carried out in the presenceof a suitable solvent or in bulk. Nonrestrictive examples of suitablesolvents are hydrocarbons which may be halogenated, e.g. benzene,toluene, xylene, mesitylene, ethylbenzene, chlorobenzene,dichlorobenzene, fluorobenzene, decalin, pentane, hexane, cyclohexane,dichloromethane, chloroform, tetrachloromethane, 1,2-dichloroethane ortrichloroethylene, ethers such as diethyl ether, di-n-butyl ether, MTBE,THF, DME, anisole, triglyme or dioxane, amides such as DMF,dimethylacetamide or NMP, sulfoxides such as DMSO, phosphoramides suchas hexamethylphosphoramide, urea derivatives such as DMPU, ketones suchas acetone or ethyl methyl ketone, esters such as ethyl acetate,nitriles such as acetonitrile and also any mixtures of these.

The process of the present invention is generally carried out at from−100° C. to +500° C., preferably from −78° C. to +200° C., particularlypreferably from 0° C. to 100° C.

The reaction can be carried out in a single-phase system or in amultiphase system.

The molar ratio of reagent EY to metallocene (Ia) is generally in therange from 0.5 to 100, preferably from 1 to 10.

The concentration of metallocene (Ia) or of reagent EY in the reactionmixture is generally in the range from 0.001 mol/l to 8 mol/l,preferably in the range from 0.01 to 3 mol/l, particularly preferably inthe range from 0.1 mol/l to 2 mol/l.

The duration of the reaction of metallocenes of the formula (Ia) with areagent EY is generally in the range from 5 minutes to 1 week,preferably in the range from 15 minutes to 48 hours.

The catalyst system of the present invention may, if desired, furthercomprise additional additive components. It is also possible to usemixtures of two or more metallocene compounds of the formula (I) ormixtures of metallocene compounds of the formula (I) with othermetallocenes or semisandwich compounds, e.g. for preparing polyolefinshaving a broad or multimodal molar mass distribution.

The catalyst system of the present invention is prepared by mixing atleast one metallocene of the formula (I), at least one cocatalyst and atleast one passivated support.

To prepare the supported catalyst system, at least one of theabove-described metallocene components in a suitable solvent is broughtinto contact with at least one cocatalyst component, preferably giving asoluble reaction product, an adduct or a mixture.

The composition obtained in this way is then mixed with the dehydratedor passivated support material, the solvent is removed and the resultingsupported metallocene catalyst system is dried to ensure that thesolvent is completely or mostly removed from the pores of the supportmaterial. The supported catalyst is obtained as a free-flowing powder.

A process for preparing a free-flowing and, if desired, prepolymerizedsupported catalyst system comprises the following steps:

a) Preparation of a metallocene/cocatalyst mixture in a suitable solventor suspension medium, where the metallocene component has one of theabove-described structures,

b) Application of the metallocene/cocatalyst mixture to a porous,preferably inorganic dehydrated support,

c) Removal of the major part of the solvent from the resulting mixture,

d) Isolation of the supported catalyst system,

e) If desired, prepolymerization of the supported catalyst systemobtained using one or more olefinic monomer(s) in order to obtain aprepolymerized supported catalyst system.

Preferred solvents for the preparation of the metallocene/cocatalystmixture are hydrocarbons and hydrocarbon mixtures which are liquid atthe reaction temperature chosen and in which the individual componentspreferably dissolve. However, the solubility of the individualcomponents is not a prerequisite, as long as it is ensured that thereaction product of metallocene and cocatalyst component is soluble inthe solvent chosen. Examples of suitable solvents include alkanes suchas pentane, isopentane, hexane, heptane, octane and nonane; cycloalkanessuch as cyclopentane and cyclohexane; and aromatics such as benzene,toluene, ethylbenzene and diethylbenzene. Very particular preference isgiven to toluene.

The amounts of aluminoxane and metallocene used in the preparation ofthe supported catalyst system can be varied over a wide range.Preference is given to setting a molar ratio of aluminum to transitionmetal in the metallocene of from 10:1 to 1000:1, very particularlypreferably from 50:1 to 500:1. In the case of methylaluminoxane,preference is given to using 30% strength solutions in toluene, but theuse of 10% strength solutions is also possible.

For preactivation, the metallocene in the form of a solid is dissolvedin a solution of the aluminoxane in a suitable solvent. It is alsopossible to dissolve the metallocene separately in a suitable solventand subsequently to combine this solution with the aluminoxane solution.Preference is given to using toluene.

The preactivation time is from 1 minute to 200 hours.

The preactivation can take place at room temperature (25° C.). The useof higher temperatures may in some cases shorten the preactivation timerequired and effect an additional increase in the activity. In thiscase, higher temperature means a temperature in the range from 50 to100° C.

The preactivated solution or the metallocene/cocatalyst mixture issubsequently combined with an inert support material, usually silicagel, which is in the form of a dry powder or as a suspension in one ofthe abovementioned solvents. The support material is preferably used aspowder. The order of addition is immaterial. The preactivatedmetallocene/cocatalyst solution or the metallocene/cocatalyst mixturecan be added to the support material, or else the support material canbe introduced into the solution.

The volume of the preactivated solution or the metallocene/cocatalystmixture can exceed 100% of the total pore volume of the support materialused or else can be up to 100% of the total pore volume.

The temperature at which the preactivated solution or themetallocene/cocatalyst mixture is brought into contact with the supportmaterial can vary in a range from 0 to 100° C. However, lower or highertemperatures are also possible.

Subsequently, the solvent is completely or mostly removed from thesupported catalyst system, during which the mixture can be stirred and,if desired, also heated. Preference is given to removing both thevisible proportion of the solvent and also the proportion in the poresof the support material. Removal of the solvent can be carried out in aconventional way using reduced pressure and/or flushing with inert gas.In the drying procedure, the mixture can be heated until the freesolvent has been removed, which usually takes from 1 to 3 hours at apreferably selected temperature in the range from 30 to 60° C. The freesolvent is the visible proportion of solvent in the mixture. For thepurposes of the present invention, residual solvent is the proportionwhich is enclosed in the pores.

As an alternative to complete removal of the solvent, the supportedcatalyst system can also be dried only to a certain residual solventcontent, with the free solvent having been completely removed. Thesupported catalyst system can subsequently be washed with a low-boilinghydrocarbon such as pentane or hexane and dried again.

The supported catalyst system prepared according to the presentinvention can either be used directly for the polymerization of olefinsor be prepolymerized using one or more olefinic monomers before use in apolymerization process. The prepolymerization procedure for supportedcatalyst systems is described, for example, in WO 94/28034.

As additive, a small amount of olefin, preferably an α-olefin (forexample styrene or phenyldimethylvinylsilane), as activity-increasingcomponent or, for example, an antistatic (as described in U.S. Ser. No.08/365280) can be added during or after the preparation of the supportedcatalyst system. The molar ratio of additive to metallocene componentcompound I is preferably from 1:1000 to 1000:1, very particularlypreferably from 1:20 to 20:1.

The present invention also describes a process for preparing apolyolefin by polymerization of one or more olefins in the presence ofthe catalyst system of the present invention comprising at least onetransition metal component of the formula (I). For the purposes of thepresent invention, the term polymerization encompasses bothhomopolymerization and copolymerization.

Preference is given to polymerizing olefins of the formulaR_(m)—CH═CH—R_(n), where R_(m) and R_(n) are identical or different andare each a hydrogen atom or an organic radical having from 1 to 20carbon atoms, in particular from 1 to 10 carbon atoms, and R_(m) andR_(n) together with the atoms connecting them can form one or morerings.

Examples of such olefins are 1-olefins having 2-40 carbon atoms,preferably from 2 to 10 carbon atoms, e.g. ethene, propene, 1-butene,1-pentene, 1-hexene, 4-methyl-1-pentene or 1-octene, styrene, dienessuch as 1,3-butadiene, 1,4-hexadiene, vinylnorbornene, norbornadiene orethylnorbornadiene, and cyclic olefins such as norbornene,tetracyclododecene or methylnorbornene. In the process of the presentinvention, preference is given to homopolymerizing propene or ethene orcopolymerizing propene with ethene and/or with one or more 1-olefinshaving from 4 to 20 carbon atoms, e.g. hexene, and/or one or more dieneshaving from 4 to 20 carbon atoms, e.g. 1,4-butadiene, norbornadiene,ethylidenenorbornene or ethyinorbornadiene. Examples of such copolymersare ethene-propene copolymers or ethene-propene-1,4-hexadieneterpolymers.

The polymerization is carried out at from −60 to 300° C., preferablyfrom 50 to 200° C., very particularly preferably 50-80° C. The pressureis from 0.5 to 2000 bar, preferably from 5 to 64 bar.

The polymerization can be carried out in solution, in bulk, insuspension or in the gas phase, continuously or batchwise, in one ormore stages.

The catalyst system prepared according to the present invention can beused as sole catalyst component for the polymerization of olefins havingfrom 2 to 20 carbon atoms, but is preferably used in combination with atleast one alkyl compound of an element of main groups I to III of thePeriodic Table, e.g. an aluminum alkyl, magnesium alkyl or lithium alkylor an aluminoxane. The alkyl compound is added to the monomer orsuspension medium and serves to free the monomer of substances which canadversely affect the catalyst activity. The amount of alkyl compoundadded depends on the quality of the monomers used.

If necessary, hydrogen is added as molar mass regulator and/or toincrease the activity.

In addition, an antistatic can be metered into the polymerization systemduring the polymerization, either together with or separately from thecatalyst system used.

The polymers prepared using the catalyst system of the present inventiondisplay a uniform particle morphology and contain no fines. No depositsor caked material occur in the polymerization using the catalyst systemof the present invention.

The catalyst system of the present invention gives polymers, e.g.polypropylene, having extraordinarily high stereospecificity andregiospecificity.

A particularly characteristic parameter for the stereospecificity andregiospecificity of polymers, in particular polypropylene, is the triadtacticity (TT) and the proportion of 2-1-inserted propene units (RI)which can both be determined from the ¹³C-NMR spectra.

The ¹³C-NMR spectra are measured at elevated temperature (365 K) in amixture of hexachlorobutadiene and d₂-tetrachloroethane. The resonancesignal of d₂-tetrachloroethane (δ=73.81 ppm) is used as internalreference for all the ¹³C-NMR spectra of the polypropylene samplesmeasured.

To determine the triad tacticity of polypropylene, the methyl resonancesignals in the ¹³C-NMR spectrum from 23 to 16 ppm are examined; cf. J.C. Randall, Polymer Sequence Determination: Carbon-13 NMR Method,Academic Press New York 1978; A. Zambelli, P. Locatelli, G. Bajo, F. A.Bovey, Macromolecules 8 (1975), 687-689; H. N. Cheng, J. A. Ewen,Makromol. Chem. 190 (1989),1931-1943. Three successive 1-2-insertedpropene units whose methyl groups are arranged on the same side in the“Fischer Projection” are referred to as mm triads (δ=21.0 ppm to 22.0ppm). If only the second methyl group of the three successive propeneunits points to the other side, one speaks of an rr triad (δ=19.5 ppm to20.3 ppm), and if only the third methyl group of the three successivepropene units points to the other side, of an mr triad (δ=20.3 ppm to21.0 ppm). The triad tacticity is calculated using the followingformula:

TT(%)=mm/(mm+mr+rr)·100

If a propene unit is inserted inversely into the growing polymer chain,this is referred to as a 2-1 insertion; cf. T. Tsutsui, N. Ishimaru, A.Mizuno, A. Toyota, N. Kashiwa, Polymer 30 (1989), 1350-56. The followingdifferent structural arrangements are possible:

The proportion of 2-1-inserted propene units (RI) can be calculatedusing the following formula:

RI(%)=0.5Iα,β(Iα,α+Iα,β+Iα,δ)·100,

where

Iα,α is the sum of the intensities of the resonance signals at δ=41.84,42.92 and 46.22 ppm,

Iα,β is the sum of the intensities of the resonance signals at δ=30.13,32.12, 35.11 and 35.57 ppm and

Iα,δ is the intensity of the resonance signal at δ=37.08 ppm.

The isotactic polypropylene which has been prepared using the catalystsystem of the present invention has a proportion of 2-1-inserted propeneunits RI of <0.5% at a triad tacticity TT>98.0%, and the M_(w)/M_(n) ofthe polypropylene prepared according to the present invention is from2.5 to 3.5.

The copolymers which can be prepared using the catalyst system of thepresent invention have a significantly higher molar mass than those ofthe prior art. At the same time, such copolymers can be prepared withhigh productivity using industrially relevant process parameters withoutdeposit formation by using the catalyst system of the present invention.

The invention is illustrated by the following examples which do not,however, restrict the scope of the invention.

General procedures: Preparation and handling of the organometalliccompounds was carried out with exclusion of air and moisture under argon(Schlenk technique or glove box). All solvents required were purged withargon and dried over molecular sieves before use.

EXAMPLE 1Dimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumDiiodide (1)

4.5 g (0.02 mol) of 2-methyl-7-bromo-1-indanone, 3.63 g (0.022 mol) of4-N,N-dimethylaminophenylboronic acid and 4.66 g (0.044 mol) of sodiumcarbonate together with a mixture of 80 ml of 1,2-dimethoxyethane and 25ml of water were placed in a reaction vessel, degassed a number of timesand saturated with argon. 90 mg (0.4 mmol) of palladium acetate and 0.2g (0.8 mmol) of triphenylphosphine were added and the reaction mixturewas stirred for 3 hours at 80° C. After addition of 100 ml of water, themixture was extracted with diethyl ether, the combined organic phaseswere washed with water and dried over magnesium sulfate. Removal of thesolvent and column filtration through neutral aluminum oxide(dichloromethane) gave 5.1 g of2-methyl-7-(4′-N,N-dimethylaminophenyl)-1-indanone.

¹H-NMR (300 MHz, CDCl₃): 7.58-7.24 (m, 5H), 6.78 (d, 2H), 3.38 (m, 1H),3.01 (s, 6H), 2.78-2.65 (m, 2H), 1.28 (d, 2H).

760 mg (20 mmol) of sodium borohydride were added at 0° C. to a solutionof 5.0 g (0.019 mol) of2-methyl-7-(4′-N,N-dimethylaminophenyl)-1-indanone in 100 ml ofTHF/methanol (2:1), and the mixture was stirred at room temperature for18 hours. The reaction mixture was poured into ice water, treated withconcentrated hydrochloric acid until the pH was 1, then brought to pH 9using 2 M sodium hydroxide solution and extracted a number of times withdichloromethane. The combined organic phases were washed with water andwith sodium chloride solution and dried over magnesium sulfate. Removalof the solvent gave the crude2-methyl-7-(4′-N,N-dimethylaminophenyl)-1-indanol product which wastaken up in 100 ml of toluene. After addition of 3.1 g (0.027 mol) oftrifluoroacetic acid, the mixture was stirred at 100° C. for 2 hours. 2M sodium hydroxide solution was subsequently added until the pH was 9,the phases were separated and the solvent was removed. 4.6 g of2-methyl-4-(4′-N,N-dimethylaminophenyl)indene were isolated.

¹H-NMR (300 MHz, CDCl₃): 7.46-7.21 (m, 5H), 6.86-6.81 (m, 2H), 6.72 (s,1H) 3.36 (s, 2H), 3.05 (s, 6H), 2.15 (s, 3H).

A solution of 10.0 g (40.2 mmol) of2-methyl-4-(4′-dimethylaminophenyl)indene in 100 ml of toluene and 5 mlof THF was admixed at room temperature with 16.7 ml (44 mmol) of a 20%strength solution of butyllithium in toluene and heated at 80° C. for 2hours. The suspension was subsequently cooled to 0° C. and admixed with2.76 g (21 mmol) of dimethyldichlorosilane. The reaction mixture washeated at 80° C. for another 1 hour and subsequently washed with 50 mlof water. The solvent was removed under reduced pressure and the residuewas recrystallized from heptane at −20° C. This gave 7.8 g of ligand ascolorless crystals. 5.0 g (9 mmol) of the ligand were dissolved in 70 mlof diethyl ether, admixed at room temperature with 6.84 ml (18 mmol) ofa 20% strength solution of butyllithium in toluene and subsequentlyrefluxed for 3 hours. The solvent was removed under reduced pressure andthe residue was filtered together with 50 ml of hexane through a G3Schlenk frit, washed with 50 ml of hexane and dried (0.1 mbar, 20° C.).The dilithium salt was added at −78° C. to a suspension of 2.2 g (9.5mmol) of zirconium tetrachloride in 50 ml of methylene chloride andwarmed to room temperature over a period of 18 hours while stirring. Themixture was filtered through a G3 frit and the residue was extractedwith a total of 400 ml of methylene chloride introduced a little at atime. The combined filtrates were largely freed of the solvent underreduced pressure. The crystalline solid which precipitated frommethylene chloride was separated off. 3.8 g of metallocene were obtainedas a mixture of the racemic and meso forms in a ratio of 1:1. Renewedrecrystallization from methylene chloride gave 1.4 g of the racemiccomplex in the form of yellow crystals.

¹H-NMR (300 MHz, CDCl₃): 7.62-7.00 (m, 10H), 6.88-6.76 (m, 6H), 2.95 (s,12H), 2.42 (s, 6H), 1.18 (s, 6H).

A solution of 1.0 g (1.4 mmol) ofdimethylsilanediylbis(2-methyl-4-(4′-N,N-dimethylaminophenyl)indenyl)zirconiumdichloride in a mixture of 15 ml of toluene and 15 ml of THF was admixedwith 7.95 g (5.6 mmol) of methyl iodide and the mixture was stirred at45° C. for 3 hours. The reaction mixture was subsequently evaporated todryness and the residue was washed with a little toluene and pentane,giving 1.29 g ofdimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodide(1) as a yellow-orange solid.

¹H-NMR (300 MHz, DMSO-d6): 7.70-7.05 (m, 10H), 6.89-6.79 (m, 6H), 3.51(s, 18H), 2.49 (s, 6H), 1.21 (s, 6H).

EXAMPLE 2Dimethylsilanediylbis(2-methyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumDibromide (2)

The preparation ofdimethylsilanediylbis(2-methyl-4-(4′-methylthiophenyl)indenyl)zirconiumdichloride was carried out in a manner similar to Example 1. This wassubsequently reacted with methyl bromide using a method analogous toExample 1 to give (2).

EXAMPLE 3Dimethylsilanediylbis(2-methyl-4-(3′-diphenylethylphosphoniumphenyl)indenyl)dichlorozirconiumDiiodide (3)

The preparation ofdimethylsilanediylbis(2-methyl-4-(3′-diphenylphosphinophenyl)indenyl)zirconiumdichloride was carried out in a manner similar to Example 1. This wassubsequently reacted with ethyl iodide using a method analogous toExample 1 to give (3).

EXAMPLE 4Dimethylsilanediylbis(2-methyl-4-(4′-dimethylammoniumphenyl)indenyl)dichlorozirconiumdichloride (4)

The preparation ofdimethylsilanediylbis(2-methyl-4-(4′-dimethylaminophenyl)indenyl)zirconiumdichloride was carried out in a manner similar to Example 1. This wassubsequently reacted at 0° C. with two equivalents of hydrogen chloridesolution in THF to give (4).

EXAMPLE 5Dimethylsilanediylbis(2-methyl-4-(4′-dimethyl(methoxymethyl)ammoniumphenyl)indenyl)dichlorozirconiumDichloride (5)

The preparation ofdimethylsilanediylbis(2-methyl-4-(4′-dimethyl(methoxymethyl)ammoniumphenyl)indenyl)zirconiumdichloride was carried out in a manner similar to Example 1. It wassubsequently reacted with methoxymethyl chloride (MOMCl) using a methodanalogous to Example 1 to give (5).

EXAMPLE 61,2-Ethanediylbis(2-methyl-4-(3′-dimethylammoniumphenyl)indenyl)dichlorozirconiumBistrifluoroacetate (6)

The preparation ofdimethylsilanediylbis(2-methyl-4-(3′-dimethylammoniumphenyl)indenyl)zirconiumdichloride was carried out in a manner similar to Example 1 using1,2-dibromoethane in the ligand synthesis. It was subsequently reactedat 0° C. with two equivalents of trifluoroacetic acid to give (6).

EXAMPLE 7Dimethylsilanediylbis(2-methyl-4-(4′-dimethyl-(2″-trimethylsilylethoxymethyl)ammoniumphenyl)indenyl)dichlorohafniumDichloride (7)

The preparation ofdimethylsilanediylbis(2-methyl-4-(4′-dimethyl(2″-trimethylsilylethoxymethyl)ammoniumphenyl)indenyl)hafniumdichloride was carried out in a manner similar to Example 1 usinghafnium tetrachloride in the synthesis of the complex. It wassubsequently reacted with 2-trimethylsilylethoxymethyl chloride (SEMCl)using a method analogous to Example 1 to give (7).

Polymerization Examples Preparation of the Supported Catalyst System

0.092 mmol of the appropriate metallocene was mixed with 4.3 ml of 30%strength MAO solution (20 mmol) in toluene and a further 1.9 ml oftoluene and stirred at room temperature for 1 hour while being protectedfrom light. 4 g of SiO₂ were then added while stirring and, after theaddition was complete, the mixture was stirred for another 10 minutes.Removal of the solvent in an oil pump vacuum gave a free-flowing powder.

Polymerization

A dry 16 dm³ reactor was flushed firstly with nitrogen and subsequentlywith propylene and charged with 10 dm³ of liquid propylene. 0.5 cm³ of a20% strength triisobutylaluminum solution in Varsol diluted with 30 cm³of Exxsol was then introduced into the reactor and the mixture wasstirred at 30° C. for 15 minutes. The appropriate catalyst suspension of2 g of the supported metallocene catalyst in 20 cm³ of Exxsol wassubsequently introduced into the reactor. The reaction mixture was thenheated to 60° C. (4° C./min) and the polymerization system was held at60° C. for 1 hour by cooling. The polymerization was stopped by ventingand the polymer obtained was dried under reduced pressure.

The polymerization results are shown in the following table.

Yield Activity Metallocene [kg of PP] [kg of PP/g of cat/h] Remarks 12.0 1.0 no deposit formation poly- merization occurred heterogeneously 21 .8 0.9 no deposit formation poly- merization occurred heterogeneously

We claim:
 1. A catalyst system comprising a) at least one support b) atleast one cocatalyst and c) at least one metallocene of the formula (I)

where M¹ is a transition metal of Group 4 of the Periodic Table of theElements, R¹ and R² are identical or different and are each a hydrogenatom, a halogen atom or a C₁-C₂₀ group, R³ are identical or differentand are each a hydrogen atom, a halogen atom or a C₁-C₄₀ group, and twogroups R³ may form a monocyclic or polycyclic ring system which may inturn be substituted, where at least one of the groups R¹, R², R³ bearsor is a cationic group (—DE_(L))⁺Y⁻, where D is an atom of group 15 or16 of the Periodic Table of the Elements, E are identical or differentand are each a hydrogen atom or a C₁-C₂₀ group, and two groups E mayform a monocyclic or polycyclic ring system which may in turn besubstituted, L is 3 when D is an atom of group 15 of the Periodic Tableof the Elements and is 2 when D is an atom of group 16 of the PeriodicTable of the Elements, Y is halogen, C₁-C₁₀-alkylsulfonate,C₁-C₁₀-haloalkylsulfonate, C₆-C₂₀-arylsulfonate,C₆-C₂₀-haloarylsulfonate, C₇-C₂₀-alkylarylsulfonate,C₁-C₂₀-haloalkylcarboxylate, C₁-C₁₀-alkylsulfate, tetrafluoroborate,hexafluorophosphate, hexafluoroantimonate or hexafluoroarsenate, m is aninteger less than or equal to 4 and greater than or equal to 1, m′ is aninteger less than or equal to 4 and greater than or equal to 1, k iszero or 1, with the metallocene being unbridged when k=0 and themetallocene being bridged when k=1, A is a bridge of the formula

or ═BR⁴, A^(lR) ^(₄) , —S—, —SO—, —SO₂—, ═NR₄, ═PR₄, ═P(O)R₄,o-phenylene or 2,2′-biphenylene, where M² is carbon, silicon, germanium,tin, nitrogen or phosphorus, o is 1, 2, 3 or 4, R⁴ and R⁵ are identicalor different and are each, independently of one another, a hydrogenatom, halogen or a C₁-C₂₀ group and R⁴ and R⁵ may form a monocyclic orpolycyclic ring system, X are identical or different and are each ahydrogen atom, a halogen atom, a hydroxyl group, a C₁-C₁₀-alkyl group, aC₆-C₁₅-aryl group, a C₁-C₁₀-alkoxy group, a C₆-C₁₅-aryloxy group or abenzyl group.
 2. A catalyst system as claimed in claim 1, wherein, informula (I), M₁ is titanium, zirconium or hafnium, R₁ and R² areidentical or different and are each a C₁-C₂₀-alkyl group, a C₆-C₁₄-arylgroup, a C₂-C₂₀-alkenyl group, a C₂-C₂₀-alkynyl group, aC₇-C₂₀-alkylaryl group, each of which groups may bear one or more,identical or different halogen atoms as substituents, or R¹ and R² areeach a hydrogen atom, a halogen atom, an —SiMe₃ group, or an OSiMe₃group, R³ are identical or different and are each a hydrogen atom, aC₁-C₂₀-alkyl group which may be substituted, a C₆-C₁₄-aryl group whichmay be substituted, a C₂-C₂₀-alkenyl group, a C₂-C₂₀-alkynyl group, aC₇-C₂₀-alkylaryl group, a halogen atom, an SiMe₃ group, an OSiMe₃ groupor a C₁-C₂₀-heterocyclic group which may be substituted, where the termheteroatom encompasses all elements with the exception of carbon andhydrogen, and two groups R³ may form a monocyclic or polycyclic ringsystem which may in turn be substituted, where at least one of thegroups R¹, R², R³ bears or is a cationic group (—DE_(L))⁺Y⁻, where D isnitrogen, phosphorus, oxygen or sulfur, E are identical or different andare each a hydrogen atom, a C₁-C₂₀-alkyl group, a C₆-C₁₄-aryl group, aC₂-C₂₀-alkenyl group, a C₂-C₂₀-alkynyl group, a C₇-C₂₀-alkylaryl group,a trialkylsilyl group, a triarylsilyl group or an alkylarylsilyl group,which may in turn be substituted, and two groups E may form a monocyclicor polycyclic ring system which may in turn be substituted, L is 3 whenD is an atom of group 15 of the Periodic Table of the Elements and is 2when D is an atom of group 16 of the Periodic Table of the Elements, Yis chloride, bromide, iodide, triflate, mesylate, tosylate,benzenesulfonate, trifluoroacetate, methyl sulfate, tetrafluoroborate orhexafluorophosphate, m is 1 or 2, m′ is 1 or 2, k is zero or 1, wherethe metallocene is unbridged when k=0 and the metallocene is bridgedwhen k=1, A is a bridge of the formula

 ═BR⁴, A^(lR) ^(₄) , —S—, —SO—, —SO₂—, ═NR₄, ═PR₄, ═P(O)R₄, o-phenylene,2,2′-biphenylene, where M² is carbon, silicon or germanium, o is 1 or 2,R⁴ and R⁵ are identical or different and are each, independently of oneanother, a hydrogen atom, halogen, a C₁-C₂₀-alkyl, a C₆-C₁₄-aryl, aC₁-C₁₀-alkoxy, a C₂-C₂₀-alkenyl, a C₇-C₂₀-arylalkyl, a C₇-C₂₀-alkylaryl,a C₆-C₁₀-aryloxy, a C₁-C₁₀-fluoroalkyl, a C₆-C₁₀-haloaryl, aC₂-C₁₀-alkynyl, a C₃-C₂₀-alkylsilyl, a C₃-C₂₀-arylsilyl or aC₃-C₂₀-alkylarylsilyl, and R⁴ and R⁵ may form a monocyclic or polycyclicring system.
 3. A catalyst system as claimed in claim 1, wherein, informula (I), M¹ is zirconium, R¹ and R² are identical or different andare each a hydrogen atom, methyl, ethyl, n-propyl, isopropyl, n-butyl,sec-butyl, isobutyl, tert-butyl, n-pentyl, branched pentyl, n-hexyl,branched hexyl, cyclohexyl or benzyl, R³ are identical or different andare each a hydrogen atom, methyl, ethyl, trifluoroethyl, n-propyl,isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl,octyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, tolyl, xylyl,tert-butylphenyl, ethylphenyl, trifluoromethylphenyl,bis(trifluoromethyl)phenyl, methoxyphenyl, fluorophenyl,dimethylaminophenyl, trimethylammoniumphenyl iodide,dimethylsulfoniumphenyl bromide, triethylphosphoniumphenyl triflate,naphthyl, acenaphthyl, phenanthrenyl, anthracenyl or aC₁-C₂₀-heterocyclic group which may be substituted, where the termheteroatom encompasses all elements with the exception of carbon andhydrogen, and two groups R³ may form a monocyclic or polycyclic ringsystem which may in turn be substituted, where at least one of thegroups R¹, R², R³ bears or is a cationic group (—DE_(L))⁺Y⁻, where D isnitrogen, phosphorus or sulfur, E are identical or different and areeach a hydrogen atom, methyl, ethyl, propyl, butyl, allyl, benzylmethoxymethyl, benzyloxymethyl, 2-methoxyethoxymethyl,2-trimethylsilylethoxymethyl or trimethylsilyl, L is 3 when D is an atomof group 15 of the Periodic Table of the Elements and is 2 when D is anatom of group 16 of the Periodic Table of the Elements, Y is chloride,bromide, iodide, triflate, mesylate, tosylate, benzenesulfonate,trifluoroacetate, methyl sulfate, tetrafluoroborate orhexafluorophosphate, m is 1, m′ is 1, k is zero or 1, where themetallocene is unbridged when k=0 and the metallocene is bridged whenk=1, A is a bridge of the formula

 or ═BR⁴, A^(lR) ^(₄) , —S—, —SO—, —SO₂—, ═NR₄, ═PR₄, ═P(O)R₄,o-phenylene or 2,2′-biphenylene, where M² is carbon or silicon, o is 1or 2, R⁴ and R⁵ are identical or different and are each, independentlyof one another, a hydrogen atom, halogen, methyl, phenyl or naphthyl,trimethylsilyl, triethylsilyl, tert-butyldimethylsilyl, triphenylsilyl,dimethylphenylsilyl, diphenylsilyl or diphenyl-tert-butylsilyl, and R⁴and R⁵ may form a monocyclic or polycyclic ring system.
 4. A catalystsystem as claimed in claim 1, wherein, in formula (I), A isdimethylsilanediyl, dimethylgermanediyl, ethylidene, methylethylidene,1,1-dimethylethylidene, 1,2-dimethylethylidene, tetramethylethylidene,isopropylidene, phenylmethylmethylidene or diphenylmethylidene.
 5. Acatalyst system as claimed in claim 1, wherein the metallocene has theformula (I*),

where M¹, A, R¹, k and X are as defined for formula (I) and R⁶ areidentical or different and are each a hydrogen atom, a C₁-C₂₀-alkylgroup which may be substituted, a C₆-C₁₄-aryl group which may besubstituted, a C₂-C₂₀-alkynyl group, a C₇-C₂₀-alkylaryl group, halogen,an OR⁴ group, an SiR⁴ ₃ group, an NR⁴ ₂ group or an SR⁴ group, and tworadicals R⁴ and R⁶, each or together, may form a monocyclic orpolycyclic ring system which may in turn be substituted, where R⁴ is asdefined for formula (I), and at least one of the radicals R⁶ bears acationic group (—DE_(L))⁺Y⁻, where D, E, L and Y are as defined forformula (I), q is an integer less than or equal to 5 and greater than orequal to 1, q′ is an integer less than or equal to 5 and greater than orequal to
 1. 6. A catalyst system as claimed in claim 5, wherein, informula (I*), R⁶ are identical or different and are each a hydrogenatom, methyl, ethyl, trifluoromethyl, trifluoroethyl, n-propyl,isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, pentyl, hexyl,octyl, cyclopropyl, cyclopentyl, cyclohexyl or phenyl, and at least oneof the radicals R⁶ bears a cationic group (—DE_(L))⁺Y⁻, where D, E, Land Y are as defined for formula (I), q is 1 or 2, q′ is 1 or
 2. 7. Acatalyst system as claimed in claim 1, wherein formula (I) representsdimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorotitaniumdiiodidedimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorohafniumdiiodidedimethylsilanediylbis(2-methyl-4-(3′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(2′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(3′,5′-bis(trimethylammonium)phenyl)indenyl)dichlorozirconiumtetraiodidedimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumnaphthyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumditosylatedimethylsilanediylbis(2-ethyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumditriflatedimethylsilanediylbis(2-methyl-4-(4′-dimethylammoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumbistetrafluoroboratedimethylsilanediylbis(2-methyl-4-(4′-N-methyl-N-pyrrolidinophenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(4′-dimethylammoniumphenyl)indenyl)dichlorotitaniumdichloridedimethylsilanediylbis(2-methyl-4-(4′-dimethyl(methoxymethyl)ammoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-dimethyl(2″-methoxyethoxymethyl)ammoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-dimethyl(benzyloxymethyl)ammoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-dimethyl-(2″-trimethylsilylethoxymethyl)ammoniumphenyl)indenyl)dichlorohafniumdichloridedimethylsilanediylbis(2-methyl-4-(4′-dimethylbenzylammoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-dimethylallylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-ethyl-4-(4′-dimethyl-(2″-trimethylsilylethoxymethyl)ammoniumphenyl)indenyl)dichlorohafniumdichloridedimethylsilanediylbis(2-ethyl-4-(4′-dimethylbenzylammoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-ethyl-4-(4′-dimethylallylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-ethyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-n-butyl-4-(4′-trimethylammoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-isopropyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-isobutyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumditriflatedimethylsilanediylbis(2-ethyl-4-(4′-triethylphosphoniumphenyl)indenyl)dichlorozirconiumdiiodide dimethylsilanediylbis(2-methyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-ethyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-(3′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-(2′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-(3′,5′-bis(dimethylsulfonium)phenyl)indenyl)dichlorozirconiumtetrabromidedimethylsilanediylbis(2-methyl-4-(4′-dibenzylsulfoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-(4′-methyl(methoxymethyl)sulfoniumphenyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-diallylsulfoniumphenyl)indenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-(3′-diphenylethylphosphoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(3′-trimethylphosphoniumphenyl)indenyl)dichlorozirconiumditriflatemethylphenylsilanediylbis(2-isobutyl-4-(4′-triethylammoniumphenyl)indenyl)dichlorozirconiumditosylate1,2-ethanediylbis(2-methyl-4-(3′-dimethylammoniumphenyl)indenyl)dichlorozirconiumbistrifluoroacetate1,2-ethanediylbis(2-methyl-4-(4′-dimethylsulfoniumphenyl)indenyl)dichlorozirconiumdibromide1,2-ethanediylbis(2-methyl-4-(3′-diphenylethylphosphoniumphenyl)indenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-5-trimethylammoniumindenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-5-trimethylphosphoniumindenyl)dichlorozirconiumdichloride1,2-ethanediylbis(2-methyl-4-dimethylbenzylammoniumindenyl)dichlorozirconiumdibromide1,2-ethanediylbis(2-methyl-4-phenyl-5-dimethylbenzylammoniumindenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-phenyl-6-trimethylammoniumindenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-5-dimethylsulfoniumindenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-methyl-4-(4′-(2″-trimethylammoniumethyl)phenylindenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(4′-(3″-dimethylsulfoniumpropyl)phenylindenyl)dichlorozirconiumdiiodidedimethylsilanediylbis(2-methyl-4-(3′-(2″-trimethylammoniumethyl)phenylindenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-methyl-4-(2′-trimethylammoniumethyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-(2′-trimethylammoniumethyl)indenyl)dichlorozirconiumdichloridedimethylsilanediylbis(2-(2′-trimethylammoniumethyl)-4-phenylindenyl)dichlorozirconiumdibromidedimethylsilanediylbis(2-(2′-dimethylsulfoniumethyl)-4,6-dimethylindenyl)dichlorozirconiumdiiodide or a mixture thereof.
 8. A process for preparing a polyolefinby polymerization of one or more olefins in the presence of a catalystsystem as claimed in claim 1.